In the previous chapter, we went deep into data cleaning and preparation. But what is inside this dataset? What story does it tell about the war, and how can we make those stories clear? Knowing how to dissect data, understand it, and extract insights is one of the crucial skills for data analysis and is a mandatory step before building anything driven by this data. In this chapter, we'll learn how to explore a dataset, compute aggregate statistics, and understand outliers and general trends through data visualization. The skills we'll learn are essential to any data analysis and are used throughout the industry and academia.

In particular, the following topics will be covered in this chapter:

• Descriptive statistics
• Aggregation and resampling
• The ecosystem of modern visualizations using matplotlib with pandas, altair, and datashader
• Basic data visualization with pandas and matplotlib
• Interactive charts with altair
• Visualizing millions of records with datashader